(PhysOrg.com) -- For the first time, researchers have demonstrated that an LED can emit more optical power than the electrical power it consumes. Although scientifically intriguing, the results won’t immediately result ...
(PhysOrg.com) -- Researchers from the Nichia Corporation in Tokushima, Japan, have set an ambitious goal: to develop a white LED that can replace every interior and exterior light bulb currently used in homes and offices. ...
(Phys.org) —Ann Makosinski from Victoria, British Columbia, has an LED flashlight powered by body heat. This inventor has a flashlight that glows when she holds it. The story gets more interesting, though. She is 15 years ...
In two breakthroughs in the realm of photonics, City College of New York graduate researchers are reporting the successful demonstration of an LED (light-emitting diode) based on half-light half-matter quasiparticles in atomically ...
Nanophysics
Sep 27, 2019
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1874
(Phys.org) —Light-emitting diodes, or LEDs, are the most efficient and environmentally friendly light bulbs on the market. But they come at a higher up-front price than other bulbs, especially the ones with warmer and more ...
Nanomaterials
Jun 13, 2013
0
0
A team of researchers at the University of Exeter has found that the slow conversion of outdoor lighting to LEDs across much of Europe has led to the development of a new kind of light pollution. In their paper published ...
(Phys.org)—Currently, all light-emitting diodes (LEDs) emit light of only one color, which is predefined during fabrication. So far, tuning the color of light produced by a single LED has never been realized, despite numerous ...
(PhysOrg.com) -- Researchers in the US, China, Korea and Singapore have collaborated to develop flexible ultra-thin sheets of inorganic light emitting diodes (LEDs) and photodetectors for implantation under the skin for medical ...
Light-emitting diodes (LEDs) have revolutionized modern lighting and sensing technology. From applications in our homes to industry, LEDs are used for all lighting applications, from indoor lighting over TV screens to biomedicine. ...
Optics & Photonics
Jan 9, 2024
3
103
(Phys.org) —Quantum dot LEDs (QLEDs) are a promising technology for creating large-area displays that could have applications for TVs, cell phones, and digital cameras. So far, however, the highest efficiencies of QLEDs ...
A light-emitting diode (LED) (pronounced /ˌɛliːˈdiː/, or just /lɛd/), is an electronic light source. The LED was first invented in Russia in the 1920s, and introduced in America as a practical electronic component in 1962. Oleg Vladimirovich Losev was a radio technician who noticed that diodes used in radio receivers emitted light when current was passed through them. In 1927, he published details in a Russian journal of the first ever LED.
All early devices emitted low-intensity red light, but modern LEDs are available across the visible, ultraviolet and infra red wavelengths, with very high brightness.
LEDs are based on the semiconductor diode. When the diode is forward biased (switched on), electrons are able to recombine with holes and energy is released in the form of light. This effect is called electroluminescence and the color of the light is determined by the energy gap of the semiconductor. The LED is usually small in area (less than 1 mm2) with integrated optical components to shape its radiation pattern and assist in reflection.
LEDs present many advantages over traditional light sources including lower energy consumption, longer lifetime, improved robustness, smaller size and faster switching. However, they are relatively expensive and require more precise current and heat management than traditional light sources.
Applications of LEDs are diverse. They are used as low-energy indicators but also for replacements for traditional light sources in general lighting and automotive lighting. The compact size of LEDs has allowed new text and video displays and sensors to be developed, while their high switching rates are useful in communications technology.
This text uses material from Wikipedia, licensed under CC BY-SA
